The probability that a student is chosen randomly from the class has a cat or a dog is 15/20.
Probability refers to a possibility that deals with the occurrence of random events. The probability of all the events occurring need to be 1.
The formula of probability is defined as the ratio of a number of favorable outcomes to the total number of outcomes.
P(E) = Number of favorable outcomes / total number of outcomes
The class has a cat and a dog = 9
Has a dog and does not have a cat = 2
Does not have a dog and has a cat = 4
Does not have dog and cat = 5
The total strength of the class is 20
The probability that a student is chosen randomly from the class has a cat or a dog = Number of favorable outcomes / total number of outcomes
P(E) = 15 /20
Hence, The probability that a student is chosen randomly from the class has a cat or a dog is 15/20.
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